#app {
    width: 10.14rem;
    margin: 0 auto;

    .main {
        width: 100%;

        .main-img {
            width: 100%;
        }
    }

    .adv {
        position: absolute;
        top: .3rem;
        left: .3rem;
    }
}

.toTop {
    width: .5rem;
    height: .5rem;
    position: fixed;
    right: .3rem;
    bottom: .5rem;
    background-color: #ddd;
    text-align: center;
    display: none;
}